Approach route control apparatus, including train carried control means for railway track switches and associated signals



Oct. 5, 1954 CHI CHANG CHU 2,691,093

APPROACH ROUTE CONTROL APPARATUS, INCLUDING TRAIN CARRIED CONTROL MEANS FOR RAILWAY TRACK SWITCHES AND ASSOCIATED SIGNALS 2 Sheefs-Sheet 1 Filed May 23, 1950 Q m U D W A m N? B SMQ WW m .w a W m w aw Es lL 1 U a R u i T .sww mm m m i n A m r 3 k m w W Ill 55% Ev m u NJ NE J. k w wfiwk 6 wwwwkkfim QQQBEQQRW inl a A q L N3 mm @N & awrw h kw r a N u in L WEN n n R m k w 6% m SQ .fil rl Qw .wm w mrwvw m m MN Rm ll vm Get. 5, 1954 CHI CHANG CHU 2,691,093

CONTROL APPARATUS. mcummc TRAIN APPROACH ROUTE CARRIED CONTROL MEANS FOR RAILWAY TRACK SWITCHES AND ASSOCIATED SIGNALS 2 Sheets-Sheet 2 Filed May 23, 1950 INVENTOR. 12i Chang 011a HIS ATTORNEY Patented Oct. 5, 1954 UNITED STATES PATENT OFFICE Chi Chang Chu, Pittsburgh, Pa., assignor to Westinghouse Air Brake Company, a corporation of Pennsylvania CARRIED CONTROL Application May 23, 1950, Serial No. 163,742

8 Claims.

My invention relates to approach route control apparatus for railway track switches and associated signals such, for example, as in an interlocking plant. More specifically, my invention relates to an arrangement embodying train identification means such, for example, as manually operable means carried on an approaching train or other railway vehicle for effecting operation of railway track switches and associated signals for preparing a traffic route according to a corresponding condition of such train identification means while the train or other railway vehicle on which it is carried occupies a given portion of track adjacent the railway track switches and associated signals.

It is common practice on railroads for a train which is to enter or leave a main track at a siding switch to stop while a trainman goes on ahead and operates the switch. This results in loss of time and energy, and sometimes results in damage to equipment, by stopping and starting, especially in the case of a heavy freight train.

Such losses and damage can be prevented if the track switches and associated signals are operated by power means controlled manually from a remote point such, for example, as a dispatchers ofiice, through the medium of centralized traiiic control apparatus, or from an interlocking tower or station through the medium of levers in an interlocking machine. Various arrangements have also been provided for effecting operation of isolated railway track switches to the reverse position, without stopping the train, by manually operable means carried on the engine of an approaching train. Such arrangements have embodied trackway inductor means cooperating with train-carried inductor means, trackway sound responsive means controlled by whistle sounds, trackway means responsive to blasts of air from the passing train, trackway light responsive means, timing means, and trackway ramps or contact rails.

An object of my invention is the provision of novel and improved means for effecting operation of railway track switches and associated signals from an approaching train, for preparing various traffic routes without stopping the train, under certain conditions such, for example, as where there is no centralized control system or where the traffic over a group of switches is such that it is not considered to require the continuous services of a leverman in an interlocking plant.

Features of my invention for attaining this object are a Wayside oscillator which becomes energized in response to the presence of a train on an approach section of track adjacent the switch, such as in an interlocking plant; traincarried receiving means which becomes operated by energy transmitted from the wayside oscillator; and a train-carried oscillator controlled by the train-carried receiving means and by train-carried identification means for supplying energy to the track rails for effecting energization of wayside receiving means which in turn may effect operation of one or more railway track switches and associated signals for preparing one or another corresponding railway traffic route.

Advantages of such an arrangement over previous arrangements for efiecting operation of a railway track switch by manually operable means carried on an approaching train are that it does not require trackway apparatus such, for example, as inductors or contact elements, located close to the track, which are subject to damage by trains, and it does not employ timing means which requires a train to occupy track sections at specific times in order to efiect operation of a railway track switch.

Another feature of my invention is that, when a given route has been prepared by means associated with a given train, an indication is displayed for giving corresponding information to the trainmen of a second train which is following the given train. The second train can, therefore, follow the preceding given train closely if the second train is to take the same route as the preceding train, or if the second train is to take a difierent route, it can stop on a given approach section and Wait until the preceding train has moved off of a portion of the given route, and a different indication will then be displayed for informing the operator of the following train that the route he is to take is being prepared.

I shall describe one form of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

The accompanying drawings, Figs. 1a and 117, when placed end to end, with Fig. la on the left, constitute a diagrammatic view showing one form of apparatus embodying my invention, in which railway vehicle carried apparatus includes a re ceiver which is inductively controllable by current of a first given character in the rails of a track which is occupied by a vehicle on which the apparatus is carried; in which the vehicle carried apparatus also includes an oscillator which supplies current inductively to the track rails, of a second or a third given character according to the position of a manually operable control device also carried on the railway vehicle; in which current of the first given character is supplied to the rails of an approach section of railway track by a wayside oscillator; in which a wayside receiver is selectively responsive to current of the second or third given character in the rails of the approach section for controlling a first or a second primary route control relay, respectively; in which a third and a fourth route control relay, which I shall call intermediate route control relays, are controlled in part by the first and second route control relays; in which a fifth and a sixth route control relay which are also called final route control relays are controlled in part by the third and fourth route control relays, respectively; in which a home signal is provided which is capable of displaying a first or a second proceed indication according as one or another railway traffic route is prepared; in which a distant signal is provided for the home signal; and in which route indicators adjacent the distant signal are controlled according to the route which has been prepared.

Similar reference characters refer to similar parts in the drawings.

Referring further to the drawings, a stretch of railway track is shown including a switch, designated by the reference character 3W, in Fig. 1b, which is operable to a first or a second extreme position in the preparation of various routes such, for example, as in an interlocking plant. Two such routes are shown in the drawings. Switch 3W is movable between its first and second extreme positions by any suitable power operated mechanism designated by the reference character 3WM such, for example, as the wellknown electropneumatic type, or the electric motor type.

A home signal, designated by the reference character 45, for governing traffic movements over the different routes, has an upper arm, designated by the reference character 4a, which becomes operated for directing traihc movements over a railway traffic route which includes switch 3W in the position in which it is shown in the drawing, which I shall call the first or normal extreme position. Signal IS has also a lower arm, designated by the reference character 4b, which becomes operated for directing traflic movements over a railway trafiic route which includes switch 3W in the opposite position, which I shall call the second or reverse extreme position.

At the opposite or leaving ends of the two routes shown, over which signal 48 governs traffic movements, are signals 58 and 68, which may be automatic signals, for governing trafific movements in the same direction as signal 4S, toward the right, as shown in the drawing, which I shall assume is the eastbound direction.

A distant signal 28, shown in Fig. 1a, governs eastbound trafrlc movements approaching signal 48.

A signal IS to the rear of signal 28 governs eastbound traflic movements approaching signal 2S.

Each of the signals IS, 2S, 4S, 5S and 65 may be of any suitable design such, for example, as the well-known color light type having a clear proceed lamp G, a caution proceed lamp Y, and a stop lamp R, as shown for signals IS and 2S, and for each of the two arms of signal 48.

Route indicators, designated by the reference characters NK and RK, are located adjacent signal 2S. As shown in the drawings, these route indicators are mounted on the same mast as signal 2S.

The stretch of railway track shown in the drawings is divided by insulated joints I into section IT between signals IS and 28, which I shall call an approach section, section 2T between signals 2S and 45, which I shall call a detector section, section 3T in which switch 3W is located, which I shall also call a detector section, sections MT and 412T between section 3'1 and signals 58 and 68, respectively, which I shall call route sections, and sections ST and GT, which I shall call signal sections. Each track section is provided with a track circuit including a suitable source of current, such as a battery 8, connected across the rails adjacent one end of the section, and a track relay, designated by the reference character R preceded by the reference character for the associated section, connected across the rails adjacent the opposite end of the section. An impedance 92 is connected in series with the battery 8 across the rails of section IT in order to prevent short circuiting the current from the oscillators through battery 8.

A train, or other railway vehicle, designated by the reference character V, is represented by a pair of wheels 9 and an axle I0, and is shown on a preliminary portion, designated by the reference character OT, of the track, to the rear of signal IS.

Receiving means carried on vehicle V comprises receiving coils, designated by the reference characters Ie and 2e, which are energizable by current of a first given character such, for example, as a first given frequency, in the track rails, to which receiving apparatus, designated by the reference character VRec on vehicle V, is arranged to respond for energizing an approach route relay, designated by the reference characterAUR.

An approach route stick relay, designated by the reference character AUSR, has a pickup circuit controlled by relay AUR, and a stick circuit controlled by a manually operable control device, designated by the reference character P, which is carried on vehicle V.

As shown in the drawings, the device P is a circuit controller of the push-turn type having two normally open push contacts 47 and 53, a normal turn contact, designated by the reference character n, and a reverse turn contact, designated by the reference character 1.

A whistle control valve magnet, designated by the reference character XL, carried on the vehicle, is controlled by relays AUR and AUSR, and is made slow releasing by a resistor t and a condenser 0 connected in series with each other across its winding. A whistle, designated by the reference character X, becomes sounded when the valve magnet XL becomes deenergized for more than a brief release period of time.

A suitable source of current such, for example, as a battery designated by the reference character VQ, having a positive terminal VB and a negative terminal VN, is carried on vehicle V. Another suitable source of current such, for example, as a battery Q having a positive terminal B and a negative terminal N, is located adjacent the track.

Transmitting means, carried on vehicle V, comprises an oscillator designated by the reference character VOsc which is controlled by relays AUSR and AUR and by circuit controller P for supplying transmitting coils, designated by the reference characters I2 and 2i, with energizing current of a second or a third given character such, for example, as a second or a third given frequency according as control device P is in its 11. or its 7' position, respectively. Coils Ii and 22' in turn induce current of corresponding character in the rails of the track which is occupied by vehicle V.

Wayside transmitting means comprises an oscillator, designated by the reference character TOsc, which is connected across the rails of section IT adjacent signal 25 for supplying current of a first given character to which the vehicle carried receiver VRec is responsive for energizing relay AUR when vehicle V occupies section IT.

Wayside receiving means comprises receiving apparatus, designated by the reference character TRec, which is also connected across the rails of section IT adjacent signal 28 and is responsive to current of the second and third given characters in the rails of section IT for energizing a first or a second primary route control relay, designated by the reference characters NUR and RUR, respectively.

A third and a fourth route control relay, designated by the reference characters ZNR. and ZRR respectively, which I shall call intermediate route control relays, are controlled in part by the primary route control relays.

A fifth and a sixth route control relay, designated by the reference characters SNR and SEE, respectively, which I shall call final route control relays, are in turn controlled in part by the intermediate route control relays.

A polarized route control relay, designated by the reference character 3NRWR, which, upon becoming deenergized, retains its contacts closed in the last energized position, is controlled by relays 3NR and SEE.

A polarized switch control relay, designated by the reference character SWR, which, uponbecoming deenergized, retains its contacts closed in the last energized position, is controlled in its first or second extreme position, respectively.

Each of the signals IS and 2S, and each arm of signal 48 is shown controlled by a polarized signal relay of the retained neutral type, in which the neutral contacts are slow to pick up and slow to release. Each of the polarized signal relays is designated by the reference character HDR preceded by the numeral in the reference character for the associated signal.

A slow release approach lighting relay, designated by the reference character ZAER, for signal 28, is controlled in series with relay IHDR for signal IS.

An approach repeater relay, designated by the reference character ZAEPR, is controlled by relay 2AER and by relays 2NR and ZRR. Relay ZAEPR is made slow releasing by a resistor t and a condenser 0 connected in series with each other across the winding of relay ZAEPR.

An approach stick relay, designated by the reference character ZAESR, is controlled by relays ZAER, ZHDR, ZNR and 2BR.

Having described, in general, the arrangement and the control of the various parts of apparatus embodying my invention, I shall now describe the circuits and operation in detail.

As shown in the drawings, all parts of the apparatus are in the normal condition, that is, the track sections are unoccupied, and therefore all track relays are energized; each of the arms 4a and 4b of signal 4S is displaying the red or stop indication; signal 25 is unlighted but its control relay ZHDR is energized by current of reverse polarity for controlling signal 28 to display the yellow or caution proceed indication; signal IS is displaying the green or clear proceed indication; switch 3W is in its first extreme, or normal, position for preparing the route between signals 4S and 58; the vehicle-carried and the wayside oscillators and receivers are all deenergized; the vehicle-carried circuit controller P is in its normal condition in which its front contacts 4'! and 53' and its reverse contact 1' are open and its normal contact n is closed; relays IHDR and BWR are energized by current of normal polarity; relay 2HDR is energized by current of reverse polarity; relays 2AER, 2AEPR and SNWCR and whistle valve magnet XL are energized; and relays AUR, AUSR, NUR, RUR, ZNR, ZRR, ZAESR, 3NR, SRR, 3NRWR, 3'IPSR, 3RWCR, 4aHDR and dbHDR are deenergized.

The circuit by which relay SNWCR is energized passes from terminal B, through contact ll of relay 3WR closed in the normal position, contact I2 of switch 3W closed in the first extreme or normal position, and the winding of relay SNWCR, to terminal N.

The circuit by which relay SWR is energized by current of normal polarity passes from terminal B, through contact 13 of relay lbI-IDR, contact M of relay 3TB, contact l5 of relay 3NRWR closed in the normal position, winding of relay 3W8, contact it of relay SNRWR closed in the normal position, and contact ll of relay 4aI-IDR. to terminal N.

The circuit by which relay ZHDR is energized by current of reverse polarity passes from terminal B, through contact is of relay 3TB, back point of contact 19 of relay 4al-IDR, back point of contact 20 of relay lbHDR, contact 2| of relay ZTR, winding of relay 2HDR, back point of contact 22 of relay lbHDR, and the back point of contact 23 of relay :laI-IDR to terminal N.

The circuit by which relays lI-IDR and ZAER are energized by current of normal polarity passes from terminal B, through the winding of relay ZAER, contact 25 of relay 2TH, front point of contact 25 of relay ZHDR, contact 26 of relay ITR, winding of relay IHDR, and the front point of contact 2? of relay ZHDR to terminal N.

The circuit by which relay ZAEPR is energized passes from terminal B, through the front point of contact 28 of relay ZAER, and the winding of relay ZAEPR in multiple with a series connection through resistor t and condenser c, to terminal N.

The circuit by which green lamp G of signal IS is lighted passes from terminal B, through the front point of contact 31 of relay IHDR, contact 32 of relay lI-IDR closed in the normal position, and lamp G of signal IS to terminal N. The red lamp of arm 4a of signal 48 is energized by a circuit passing from terminal B, through the back point of contact 33 of relay GaHDR, and lamp R. of arm 4a to terminal N. Red lamp R of arm db of signal AS is energized by a circuit which is similar to the circuit just traced for lamp R of arm 4a.

The whistle control valve magnet XL of vehicle V, shown in Fig. 1a, is energized by a circuit passing from terminal VB, through contact 49 of relay AUSR, and the winding of magnet XL in multiple with a circuit path through a resistor t and a condenser c to terminal VN.

I shall assume that, with apparatus embodying my invention arranged as shown in the accompanying drawings, a trainman or other operator on vehicle V moves the circuit controller P to the pushed-in position, thereby closing contacts 4! and 53, and leaves the circuit controller in the normal turn position in which contact 11 remains closed.

I shall assume further that the vehicle operator then drives vehicle V onto approach section IT, causing track relay ITR to become deenergized. Contact 26 of relay ITR, then opens the circuit previously traced for relay iHDR, causing relay lHDR to become deenergized. Contact 3d of relay IHDR then opens the circuit previously traced for lamp G of signal IS, and closes a circuit for lighting lamp R of signal is, passing from terminal B, through the back point of contact 3| of relay lI-IDR, and lamp R of signal IS to terminal N.

Relay ZAER, which is in series with relay lI-lZDR, also becomes deenergized by the opening of contact 26 of relay iTR. Upon the lapse of a brief interval of time, contact 28 of relay ZAER opens at its front point, thereby deenergizing relay EAEPR.

Contact 28 of relay ZAER, upon becoming closed at its back point, completes a circuit for lighting lamp Y of signal 28, this circuit passing from terminal B, through the back point of contact 28 of relay ZAER, front point of contact 31 of relay ZI-HDR, contact 38 of relay ZHDR, closed in the reverse position, and lamp Y of signal 28, to terminal N.

Upon the closing of contact 42 of relay 2AER, relay ZAES-R becomes energized by a pickup circuit passing from terminal B, through contact 39 of relay ZNR, contact 48 of relay ZRR, the winding of relay ZAESR, contact 42 of relay ZAER, and the front point of contact 43 of relay ZHDR to terminal N. Relay 2AESR then completes its own stick circuit, which is the same as the pickup circuit just traced except that it includes contact 4| of relay 2AESR instead of contacts 39 and of relays ZNR and ZRR, respectively.

Upon the closing of contact of relay ZAER, the wayside oscillator TOsc becomes energized by a circuit passing from terminal B, through contact 44 of relay ZAEPR, contact 45 of relay ZAER, and oscillator TOsc to terminal N. Oscillator TOsc therefore now supplies current of a first given character to the rails of section 1T.

Such current in the rails of section IT inductively energizes the receiving coils Is and 2e carried on vehicle V for in turn energizing the vehicle-carried receiving means including the receiving apparatus VRec which in turn energizes approach route relay AUR. The pickup circuit for relay AUSR then becomes closed, passing from terminal VB, through contact 46 of relay AUR, and. the winding of relay AUSR to terminal VN. Relay AUSR thereupon completes its own stick circuit passing from terminal VB, through contact 47 of controller P, contact 48 of relay AUSR, and the winding of relay AUSR to terminal VN.

When relay AUSR becomes energized, contact 49 opens the circuit previously traced for whistle control valve magnet XL. A second circuit is, however, now completed for energizing valve magnet XL, this circuit passing from terminal VB, through contact 50 of relay AUR, and the winding of magnet XL in multiple with resistor t and condenser c to terminal VN.

Upon the lapse of a brief period of time after relay ZAEPR becomes deenergized by the opening of contact 28 of relay 2AER at its front point,

contact 44 of relay ZAEPR opens the circuit previously traced for the wayside oscillator TOsc, thereby discontinuing energization of the rails of section IT by current of the first given character or frequency. The vehicle-carried receiver VRec and the relay AUR therefore become deenergized. Contact 50 of relay AUR therefore opens the second circuit traced for whistle valve magnet XL. Relay AUR will remain deenergized for only a short period, however, until relay ZAEPR becomes energized again, because of energization of relay ZNR, which will be traced presently, and since the whistle magnet XL is slow releasing, whistle X will not be sounded during this brief period.

Relay AUR, upon becoming deenergized, completes a circuit for energizing vehicle-carried oscillator VOsc, this circuit passing from terminal VB, through contact 5| of relay AUSR, contact 52 of relay AUR, contact 53 of controller P, contact 11 of controller P, and the vehicle-carried oscillator VOsc, to terminal VN. Transmitting coils Ii and 21' will therefore now be energized by oscillator VOsc for inducing current of the second given character or frequency in the rails of track section IT.

The wayside receiver TRec will respond to current of the second given character for energizing the first primary route control relay N UR. Relay NUR, upon becoming energized, completes a circuit for energizing the third route control relay ZNR, this circuit passing from terminal B, through the back point of contact 54 of relay RUR, contact 55 of relay NUR, winding of relay 2NR, contact 51 of relay 2RR, and contact 58 of relay ZAESR to terminal N. Relay ZNR then completes its own stick circuit, which is the same as the pickup circuit just traced except that it includes contact 56 of relay ZNR instead of the back point of contact 54 of relay RUR, and con tact 55 of relay NUR. Relay ZNR, upon becoming energized, completes a second circuit for energizing relay ZAEPR, this circuit passing from terminal B, through contact 29 of relay 2NR, and the winding of relay ZAEPR in multiple with resistor 75 and condenser c, to terminal N.

The wayside oscillator TOsc therefore new again becomes energized, by its circuit previously traced, for supplying current of the first given character to the rails of track section IT. The vehicle-carried receiver VRec responds to this current of the first given character for again energizing relay AUR, which in turn opens the circuit traced for energizing the vehicle-carried oscillator V030 and again completes the second circuit traced for valve magnet XL.

Relay ZNR, upon becoming energized, also completes a circuit for energizing route indicator NK, this circuit passing from terminal B, through contact 59 of relay ZNR, and route indicator NK to terminal N.

With relay 2NR energized, the fifth or final route control relay 3NR is energized by a circuit passing from terminal B, through contact 60 of relay ZPLDR, front point of contact 6| of relay 2NR, contact 62 of relay ZRR, winding of relay 3NR, and contact 63 of relay 3BR to terminal N. Relay 3NR, upon becoming energized, completes a circuit for energizing relay 3NRWR by current of normal polarity, this circuit passing from terminal B, through the back point of contact 64 of relay 3BR, contact 65 of relay SNR, and the right-hand portion of the winding of relay SNRWR to terminal N. Since contacts I5 and [5 of relay SNRWR are already closed in the normal position, there will be no change in the position of these contacts. Therefore, relay 3WR will remain energized by current of normal polarity in the circuit previously traced.

Relay 3NR, upon becoming energized, however, completes a pickup circuit for energizing relay 3TPSR, this circuit passing from terminal B, through contact 6'! of relay 3NR, contact ID of relay 3TR, and the winding of relay STPSR to terminal N. Relay 3TPSR then completes its own stick circuit passing from terminal B, through contact 69 of relay 3TPSR, contact IQ of relay 3TB, and the winding of relay 3TPSR to terminal N.

Relay STPSR, upon becoming energized, completes a circuit for energizing relay 4aHDR by current of normal polarity, this circuit passing from terminal B, through. the front point of contact II of relay 5TR, con act I2 of relay 3TPSR, contact 13 of relay dbl-IDR, the winding of relay 4aI-IDR, contact I4 of relay 3NWCR, contact 15 of relay 3TB, contact I6 of relay 4aTR, and the front point of contact ll of relay 5TR, to terminal N. With relay IaHDR thus energized by current of normal polarity, the red lamp R of the arm 4a of signal 48 will be extinguished, and green lamp G will become lighted by a circuit passing from terminal B, through the front point of contact 33 of relay lIaHDR, contact 34 of relay AaHDR closed in the normal position, and lamp G of arm 4a of signal 48 to terminal N. Relay IaI-IDR, upon becoming energized, opens its contact I'I, thereby deenergizing relay 3WR. When relay 3WR becomes deenergized, its contacts remain closed in the position to which they were last operated and therefore relay 3NWCR remains energized.

With relay AaI-IDR energized, relay ZH'DR will become energized by current of normal polarity in a circuit passing from terminal B, through contact I8 of relay 3TR, front point of contact 23 of relay daI-IDR, back point of contact 22 of relay IbHDR, the winding of relay ZHDR, contact 2I of relay 2TR, back point of contact of relay AbHDR, and the front point of contact I9 of relay IaHDR, to terminal N. With relay 2I-IDR thus energized by current of normal polarity, yellow lamp Y of signal 25 will become extinguished, and green lamp G of this signal will be lighted by a circuit passing from terminal B, through the back point of contact 28 of relay ZAER, front point of contact 31 of relay ZHDR, contact 38 of relay ZHDR closed in the normal position, and lamp G of signal 28 to terminal N.

With route indicator NK energized and signal 28 displaying the clear proceed indication, the operator of vehicle V will know that switch 3W is in its normal position and that signal arm 4a of signal 48 is displaying a proceed indication. The operator of vehicle V can therefore drive vehicle V past signal 28 at normal speed.

When vehicle V enters section 2T, relay Z'IR becomes deenergized, and therefore its contact 2I becomes opened, causing relay 2I-LDR to be deenergized. Relay ZI-IDR, upon becoming deenergized, opens the circuit previously traced for green lamp G of signal 28, and completes the circuit for red lamp R of this signal, passing from terminal B, through the back point of contact 28 of relay ZAER, back point of contact 3? of relay ZHDR, and lamp R of signal 25 to terminal N.

Relay ZHDR, upon becoming deenergized, causes relay ZAESR to in turn become deenergized, because of the opening of contact 43 of relay ZI-IDR at its front point. A second stick circuit is now completed for relay ZNR, which is the same as the stick circuit previously traced for this relay except that it includes the back point of contact 43 of relay 2HDR instead of contact 58 of relay 2AESR. The first stick circuit for relay ZNR is now open at contact 58 of relay ZAESR. Relay 2NR will, however, be retained in the energized condition by the second stick circuit, so that the route indicator NK will remain energized. Relay 3NR will, however, become deenergized on account of contact 60 of relay 2HDR now being open. Relay 3NRWR will then also become deenergized by the opening of contact of relay 3NR,

When the vehicle-carried receiving coils I e and 2e have passed the insulated joints I at signal 28, the vehicle-carried receiver VRec will be deenergized. With relay AUR thereby also deenergized, and with relay AUSR still energized by its stick circuit, if the operator of vehicle V has not already restored control device P to its pulledout position, the whistle control valve magnet XL will be deenergized, causing whistle X to be sounded. The operator of vehicle V will therefore now pull control device P out to its normal position, thereby opening its contacts 41 and 53 and deenergizing relay AUSR and the vehiclecarried oscillator VOsc. With relay AUSR deenergized, the circuit first traced for whistle control valve magnet XL will again be closed, and therefore magnet XL will discontinue the sounding of whistle X. The operator of vehicle V could, however, have restored controller P to its normal position as soon as route indicator NK became energized, because relay ZNR will be retained in its energized condition by its stick circuit after having become energized by relay NUR having completed a pickup circuit for relay ZNR.

When vehicle V leaves section IT, relay IHDR will become energized by current of reverse polarity in a circuit passing from terminal B, through the winding of relay 2AER, back point of contact 21 of relay ZHDR, winding of relay IHDR, contact 25 of relay ITR, and the back point of contact 25 of relay Zl-IDR to terminal N.

Relay ZAER, on account of being included inseries with relay il-IDR, will also be energized, thereupon opening its contact 45 and deenergizing the wayside oscillator TOsc. With relay IHDR energized by current of reverse polarity after vehicle V leaves section IT, lamp R of signal IS will be extinguished, and lamp Y of this signal will now be lighted by a circuit passing from terminal B, through the front point of contact 3I of relay IHDR, contact 32 of relay IHDR closed in the reverse position, and lamp Y of signal IS to terminal N.

When vehicle V enters section 3T, relay 3TR will become deenergized, causing relays 4aHDR and STPSR to in turn also become deenergized. With relay 4aI-lDR deenergized, green lamp G of the arm 4a of signal its will be extinguished and red lamp R of this signal arm will again be lighted by its circuit previously traced.

When vehicle V leaves section 2T, relay ZHDR will still remain deenergized on account of relay 3TR being deenergized. With relay ZHDR deenergized, relay ZNR will be retained in the energized position, and therefore route indicator NK will remain energized, and red lamp R of signal 23 will remain extinguished as long as relay TAER remains energized because of section IT being unoccupied.

When vehicle V enters section 4aT, relay 4aTR will become deenergized, so that the circuit for 11 relay 'SaI-IDR will now be open at contact 16 of relay -aTR as well as at contact 15 of relay 3TB.

When vehicle V leaves section 3T, relay daHDR will remain deenergized on account of contact of relay llaTR. being open. Relay ZHDR will, however, new again be energized by current of reverse polarity in its circuit previously traced. With relay QHDR energized, relay lI-IDR will again become energized by current of normal polarity in the circuit previously traced, causing yellow lamp Y of signal [S to be extinguished and green lamp G of signal IS to again be lighted by the circuit previously traced. Relay ZHDR, upon becoming energized, opens its contact 43 at the back point, thereby deenergizing relay ZNR. The operator of a following train could therefore now effect energization of relay ERR, for causing operation of switch W to the second or reverse extreme position, if he so desired. With relay ZNR, deenergized, relay 3NR will remain deenergized.

When vehicle V enters section 5T, relay 5TB will become deenergized, so that its pole-changing contacts H and H will become closed at their back points.

When vehicle V leaves section la'I', relay laI-IDR will still remain deenergized on account of relay 3TPSR being deenergized.

When vehicle V leaves section 5T, relay 5TB will again become energized, 50 that all parts of the apparatus will then again be in the normal position.

I shall next assume that, with all parts again in the normal condition, a train or other vehicle, equipped as shown for vehicle V, arrives on portion OT of the stretch of railway track, and that the engineman or operator pushes the controller P in to close its contacts 41 and 53, and rotates it to close contact 1'.

When the train now enters section lT, the wayside oscillator TOsc will become energized, as previously described, causing the train-carried receiver VRec and, in turn, relays AUR and AUSR to also become energized. Relay AUR, upon again becoming deenergized, as previously described, will complete a second circuit for energizing the vehicle-carried oscillator VOsc, this circuit passing from terminal VB, through contact 5| of relay AUSR, contact 52 of relay AUR, contact 53 of controller P, contact 7' of controller P, and oscillator VOsc to terminal VN. Current of the third given character will therefore now be induced in the rails of track section IT by transmitting coils l2 and 22.

In response to current of the third given character in the rails of section lT, the wayside receiver 'IRec will energize relay RUR. Relay RUR, will thereupon complete a circuit for energizing relay ZRR, this circuit passing from terminal B, through the front point of contact 54 of relay BUR, contact 78 of relay NUR, contact 80 of relay 2NR, winding of relay 2BR, and contact 58 of relay EAESR to terminal N. Relay 2BR will then complete its stick circuit which is the same as the pickup circuit just traced except that it includes contact 19 of relay 2BR instead of the front point of contact 54 of relay RUR and contact 18 of relay NUR.

When relay 2BR becomes energized, route indicator RK becomes energized by a circuit passing from terminal 13, through contact 8! of relay 2BR, and route indicator RK to terminal N. The engineman will then know that a route is being prepared over switch 3W in the reverse position.

With relay 2BR energized, relay 3BR will be energized by a circuit passing from terminal B, through contact 6!! of relay 2HDR, back point of contact 6| of relay ZNR, contact 32 of relay 2BR, contact 83 of relay SNR, and the winding of relay 3RR to terminal N.

With the relay 3BR energized, relay 3TPSR will now be energized by a second pickup circuit, passing from terminal B, through contact 68 of relay 3BR, contact 10 of relay 3TB, and the winding of relay 3TPSR to terminal N. Also, with relay 3BR energized, relay 3NRWR will be energized by current of reverse polarity in a circuit passing from terminal B, through the front point of contact 64 of relay 3BR, contact 66 of relay 3NR, and the left-hand portion of the Winding of relay BNRWR, as shown in the drawing, to terminal N.

Relay 3WR will then become energized by current of reverse polarity in a circuit which is the same as the circuit previously traced for this relay except that it includes contacts l5 and I6 of relay 3NRWR in their reverse positions instead of in their normal positions. With relay 3WR energized by current of reverse polarity, the mechanism 3WM will become energized by a circuit passing from terminal B, through contact 84 of relay 3WR in its reverse position, and mechanism 3WM to terminal N. Mechanism 3WM will therefore move switch 3W to the reverse position for preparing a route which includes section 4bT. With contact ll of relay 3WR closed in the reverse position, relay 3NWCR will be deenergized and relay 3RWCR will become energized, when switch 3W reaches its reverse position, by a circuit passing from terminal B, through contact H of relay 3WR in its reverse position, contact I2 of switch 3W closed in the reverse position of switch SW, and the winding of relay 3RWCR to terminal N.

Relay 4bI-IDR will now be energized by current of normal polarity in a circuit passing from terminal B, through the front point of contact 85 of relay BTR, contacts 86, 81, 88, and 89 of relays 4bTR, 3TB, 3RWCR, and laI-IDR, respectively, the winding of relay dbHDR, contact 90 of relay 3TPSR, and the front point of contact 9| of relay GTR to terminal N. With relay lbHDR energized by current of normal polarity, the red lamp R of arm 42) of signal 48 will be extinguished, and lamp G of arm 41) will be lighted by a circuit which is similar to the circuit previously traced for lamp G of arm 4c of signal 48.

With relay AbHDR energized, relay ZHDR will become energized by current of normal polarity in a circuit which is similar to the circuit previously traced for energizing this relay by current of normal polarity except that it includes the front points of contacts 20 and 22 of relay dbl-IDR and the back points of contacts l9 and 23 of relay :laHDR instead of the front points of contacts (9 and 23 of relay 4aHDR and the back points of contacts 20 and 22 of relay 4bHDR. Green lamp G of signal 2S will therefore again be lighted, as previously described.

I shall next assume that the train proceeds onto section 2T, and then leaves section IT. I shall assume further that, while the train is on section 2T, a second train, equipped as shown for vehicle V, arrives on portion OT of the track, and that the operator of the second train desires to follow the first train over switch 3W in the reverse position. As long as the first train occupies section 2T or section 3T, relay 2HDR will be deenergized, and therefore relay 2BR will be retained energized by its stick circuit, and route indicator RK will remain energized. The second train can therefore pass signal 28, although signal 28 is indicating stop, because route indicator RK is energized.

If the operator of the second vehicle desires to move over switch 3W in the normal position, he will push the circuit controller P in while his train is still on portion OT of the track, and will leave it in the n position, before entering section IT. After the first train has left section IT, signal IS will display the caution proceed indication, as previously described, and therefore the second train can enter section IT. The wayside oscillator TOsc, the vehicle-carried received VRec, relays AUR and AUSR, the vehicle-carried oscillator VOsc, and relay NUR will then all again become energized, as previously described. As long as the first train or vehicle remains on section 2T or section 3T, relay 2BR will be retained energized, so that relay ZNR cannot become energized for effecting operation of switch 3W to the normal position.

As soon as the first train leaves section 3T, While the second train is at any point on section IT, the control of switch 3W by the second train will become eifective. It is not necessary for the second train to be at any particular point on section IT when the first train leaves section 3T. If the first train has not left section 3T when the second train arrives at signal 28, route indicator RK will still be energized, and therefore the second train will wait at signal 2S until the first train leaves section 3T. When the first train leaves section 3T, relay ZHDR will again become energized by current of reverse polarity, as previously described, and will cause relay 2BR to become deenergized. Relay 2AESR will then again become energized, and relay ZNR will become energized by its pickup circuit previously traced.

It follows that another advantage of my invention over previous schemes in which the control of the switch must be efiected while a railway engine or other vehicle is at a given particular point such, for example, as at the location of a trackway inductor, is that, with apparatus embodying my invention, as shown in the accompanying drawings, a second train can enter sec-- tion IT while a preceding train is on section 2T or on section 3'1, and the control of the switch by the second train will become effective as soon as the preceding train leaves section 3T while the second train is at any point on section IT.

Still another advantage of my invention is that it requires less line circuit material than previous arrangements. If a trackway inductor or contact element were located at the entrance end of section IT adjacent signal IS, where, with apparatus embodying my invention, the control of switch 3W by an approaching train becomes effective when there is no preceding train on section 2T or section 3T, additional line circuit material would be required, including additional line wires between the entrance end of section IT and signal 28.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims, without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. A railway trafilc route control system comprising in combination, receiving means carried on a train responsive to energy of a first given character in the rails of a track which is occupied by said train, means for supplying energy of said first given character to said track, transmitting means carried on said train controlled in part by said receiving means for supplying energy of a second or a third given character to the rails of said track, receiving apparatus responsive to energy of said second or said third given character received from the rails of said track, and means controlled by said receiving apparatus upon responding to said energy of said second or said third given character for preparing a first or a second railway trafiic route respectively.

2. A railway traffic route control system comprising in combination, receiving means carried on a railway vehicle responsive to energy of a first given character in the rails of a track which is occupied by said vehicle, means for supplying energy of said first given character to the rails of said track, transmitting means carried on said vehicle controlled in part by said receiving means for supplying energy of a second or a third given character to the rails of said track, receiving apparatus responsive to energy of said second or said third given character received from the rails of said track, and means controlled by said receiving apparatus upon responding to said energy of said second or said third given character for effecting operation of a railway track switch to a normal or a reverse position respectively for preparing a first or a second railway trafic route respectively.

3. A railway traflic routecontrol system comprising in combination, receiving means carried on a railway vehicle responsive to energy of a first given character in the rails of a track section which is occupied by said vehicle, means responsive to occupancy of said track section by said vehicle for supplying energy of said first given character to the rails of said section, transmitting means carried on said vehicle controlled in part by said receiving means for supplying energy of a second given character to the rails of said section, and receiving apparatus responsive to energy of said second given character in the rails of said section for efiecting operation of a railway track switch for preparing a given railway traflic route.

4. A railway trafiic route control system comprising in combination, receiving means carried on a railway vehicle responsive to energy of a first given character in the rails of a track section which is occupied by said vehicle, means responsive to occupancy of said track section by said vehicle for supplying energy of said first given character to the rails of said section, transmitting means carried on said vehicle controlled in part by said receiving means for inductively supplying energy of a second given character to the rails of said section, and receiving apparatus responsive to energy of said second given character in the rails of said section for eifecting operation of a railway track switch for preparing a given railway traflic route.

5. In combination, a stretch of railway track including a switch and divided into an approach section and a detector section adjacent said switch, manually operable means carried on a railway vehicle, a first and a second route control relay, means controlled by a first or a second operation of said manually operable means and by said vehicle on said approach section for energizing said first or said second route control relay respectively, a third and a fourth route control relay, an approach stick relay, a pickup circuit for energizing said approach stick relay in response to a railway vehicle occupying said approach section if said third and fourth route control relays are deenergized, a stick circuit con trolled by a vehicle occupying said approach section for retaining said approach stick relay energized, a pickup circuit for each of said third and fourth route control relays controlled by said approach stick relay and by front contacts of said first and second route control relays respectively, a stick circuit for each of said third and fourth route control relays controlled by a back contact of the other and by a front contact of said approach stick relay, a second stick circuit for each of said third and fourth route control relays controlled by a back contact of the other and by a vehicle on said detector section, and means controlled by a front contact of said third or said fourth route control relay if said detector section is unoccupied for effecting operation of said switch to a first or a second position for preparing a first or a second traific route respectively.

6. In combination, a stretch of railway track including a switch, a home signal for governing traflic movements over said switch capable of displaying a stop indication and capable of displaying a first indication when said switch is in a first position for preparing a first traflic route and also capable of displaying a second indication when said switch is in a second position for preparing a second traffic route, a distant signal for governing traffic movements on said track approaching said home signal in the direction of traffic movements governed by said home signal, said distant signal capable of displaying a clear proceed indication when said home signal is displaying either said first or said second indication and also capable of displaying a stop indication, a first route indicator adjacent said distant signal capable of being energized when said switch is controlled to occupy said first position, a second route indicator adjacent said distant signal capable of being energized when said switch is controlled to occupy said second position, an approach track section for said distant signal, transmitting means carried on a train, manually operable means on said train capable of controlling said transmitting means to energize the rails of said approach section by current of one or another given character when said train occupies said approach section. means controlled by current of said one given character in said approach section for eifecting operation of said switch to said first position and controlling said home signal to display said first indication and also controlling said distant signal to idsplay said clear proceed indication and effecting energization of said first route indicator, means controlled by current of said another given character in said approach section for effecting operation of said switch to said second position and controlling said home signal to display said second indication and also controlling said distant signal to display said clear proceed indication and effecting energization of said second route indicator, and traific responsive means for controlling said home and distant signals to display the stop indication when a train passes said home and distant signals respectively.

7. A railway traffic route control system comprising in combination, a stretch of railway track including a switch and an approach section, receiving means carried on a railway vehicle responsive to current of a first given character in the rails of said approach section when said railway vehicle occupies said approach section, means controlled by said vehicle upon entering said approach section for supplying current of said first given character to the rails of said approach section, a receiving relay controlled by said receiving means, a push-turn circuit controller on said vehicle, a receiving stick relay having a pickup circuit controlled by said receiving relay and having a stick circuit controlled by a front contact of said push-turn circuit controller, means controlled by a front contact of said receiving stick relay and by a back contact of said receiving relay and also by a front contact and by a normal or a reverse contact of said pushturn circuit controller for inductively supplying current of a second or a third given character respectively to the rails of said approach section, and means controlled by said current of said second or third given character in said approach section for effecting operation of said switch for preparing a first or a second railway traffic route respectively.

8. A railway trafiic route control system comprising in combination, a stretch of railway track including a switch and an approach section, receiving means carried on a railway vehicle responsive to current of a first given character in the rails of said approach section when said railway vehicle occupies said approach section, means controlled by said vehicle upon entering said approach section for supplying current of said first given character to the rails of said approach section, a receiving relay controlled by said receiving means, a push-turn circuit controller on said vehicle, a receiving stick relay having a pickup circuit controlled by said receiving relay and having a stick circuit controlled by a front contact of said push-turn circuit controller, means controlled by a front contact of said receiving stick relay and by a back contact of said receiving relay and also by a front contact and by a normal or a reversecontact of said push-turn circuit controller for inductively supplying current of a second or a third given character respectively to the rails of said approach section, a slow release whistle control valve magnet controlled by a back contact of said receiving stick relay in multiple with a front contact of said receiving relay, and means controlled by said current of said second or third given character in said approach section for effecting operation of said switch for preparing a first or a second railway traffic route respectively.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,712,981 Clark et al May 14, 1929 1,737,750 Clark et al. Dec. 3, 1929 1,763,011 Shaver June 10, 1930 1,824,139 Henry Sept. 22, 1931 1,845,175 Padmore Feb. 16, 1932 1,900,409 Sorensen Mar. 7, 1933 1,971,482 Espenschied Aug. 28, 1934 2,122,358 Preston June 28, 1938 2,124,453 Shaver July 19, 1938 2,460,597 Rodgers Feb. I, 1949 2,509,331 Brannen May 30, 1950 

